Effects of nicorandil on cardiac sympathetic nerve activity after reperfusion therapy in patients with first anterior acute myocardial infarction

Purpose Ischaemic preconditioning (PC) is a cardioprotective phenomenon in which short periods of myocardial ischaemia result in resistance to decreased contractile dysfunction during a subsequent period of sustained ischaemia. Nicorandil, an ATP-sensitive potassium channel opener, can induce PC effects on sympathetic nerves during myocardial ischaemia. However, its effects on cardiac sympathetic nerve activity (CSNA) and left ventricular remodelling have not been determined. In this study, we sought to determine whether nicorandil administration improves CSNA in patients with acute myocardial infarction (AMI).Methods We studied 58 patients with first anterior AMI, who were randomly assigned to receive nicorandil (group A) or isosorbide dinitrate (group B) after primary coronary angioplasty. The nicorandil or isosorbide dinitrate was continuously infused for >48 h. The extent score (ES) was determined from ^99mTc-pyrophosphate scintigraphy, and the total defect score (TDS) was determined from ²⁰¹Tl scintigraphy 3–5 days after primary angioplasty. The left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF) were determined by left ventriculography 2 weeks later. The delayed heart/mediastinum count (H/M) ratio, delayed TDS and washout rate (WR) were determined from ¹²³I-meta-iodobenzylguanidine (MIBG) images 3 weeks later. The left ventriculography results were re-examined 6 months after treatment.Results Fifty patients originally enrolled in the trial completed the entire protocol. After treatment, no significant differences were observed in ES or left ventricular parameters between the two groups. However, in group A (n=25), the TDSs determined from ²⁰¹Tl and ¹²³I-MIBG were significantly lower (26±6 vs 30±5, P<0.01, and 32±8 vs 40±6, P<0.0001, respectively), the H/M ratio significantly higher (1.99±0.16 vs 1.77±0.30, P<0.005) and the WR significantly lower (36%±8% vs 44%±12%, P<0.005) than in group B (n=25). Moreover, 6 months after treatment, LVEDV and LVEF were better in group A than in group B.Conclusion These findings indicate that nicorandil can have beneficial effects on CSNA and left ventricular remodelling in patients with first anterior AMI.     

Prognostic value of serial cardiac 123I-MIBG imaging in patients with stabilized chronic heart failure and reduced left ventricular ejection fraction.

Many studies have shown that a one-time 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphic study during a stable period is useful for determining the prognosis of patients with chronic heart failure (CHF). However, the findings from this imaging modality are well known to be improved by medical treatment for heart failure. Accordingly, this study was performed to determine whether serial 123I-MIBG scintigraphic studies represent a reliable prognostic marker for patients with CHF. METHODS: A total of 208 patients with CHF (left ventricular ejection fraction [LVEF] < 45%) and with no cardiac events for at least 5 mo were identified on the basis of a history of decompensated acute heart failure requiring hospitalization. The delayed percentage of denervation (% denervation), delayed heart-to-mediastinum count (H/M) ratio, and washout rate (WR) were determined from the patients' 123I-MIBG images just before they left the hospital and after they had received 6 mo of treatment. The left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and LVEF were also determined by echocardiography at the same time points. RESULTS: Of the 208 patients, 56 experienced fatal cardiac events during the study. The mean follow-up period was 4.45 +/- 1.82 y. The baseline H/M ratio and WR; follow-up % denervation, H/M ratio, and WR; Delta-% denervation, H/M ratio, and WR; baseline LVEF; follow-up LVEDV, LVESV, and LVEF; and Delta-LVEDV, Delta-LVESV, and Delta-LVEF were significantly worse in the cardiac death group. A Cox regression analysis showed that the Delta-WR was an independent predictor of cardiac death. Moreover, sudden death occurred in 13 of the 56 patients with cardiac death. A Cox regression analysis also showed that the Delta-WR was an incremental predictor of sudden death. The cardiac death-free rate and sudden death-free rate were significantly higher in patients with Delta-WR less than -5% and Delta-WR less than -2% than in patients with Delta-WR greater than or equal to -5% and Delta-WR greater than or equal to -2%. CONCLUSION: Delta-WR obtained from serial 123I-MIBG scintigraphic studies can be useful for predicting cardiac death and sudden death in stabilized patients with CHF.     

Additive effects of spironolactone and candesartan on cardiac sympathetic nerve activity and left ventricular remodeling in patients with congestive heart failure.

The activation of the renin-angiotensin-aldosterone system prevents the uptake of norepinephrine in the myocardium. However, the additive effects of combined spironolactone and candesartan on cardiac sympathetic nerve activity (CSNA) have not been determined. We investigated the effects of the angiotensin-receptor blocker candesartan alone and in combination with spironolactone on CSNA in patients with congestive heart failure (CHF). METHODS: Fifty patients with CHF (left ventricular ejection fraction [LVEF] < 45%) were randomly assigned to candesartan plus spironolactone (group A; n = 25) or to candesartan alone (group B; n = 25). All patients were also treated with a loop diuretic. The delayed percent denervation, delayed heart-to-mediastinum count (H/M) ratio, and washout rate (WR) were determined from (123)I-metaiodobenzylguanidine (MIBG) scintigraphy, and plasma brain natriuretic peptide (BNP) concentration was measured before and 6 mo after treatment. The LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and LVEF were also determined by echocardiography. RESULTS: After 6 mo, all of these parameters were improved in both groups. However, the degree of change in the percent denervation was -14 +/- 12 in group A and -7 +/- 10 in group B (P < 0.05); the change in the H/M ratio was 0.19 +/- 0.18 in group A and 0.08 +/- 0.14 in group B (P < 0.05), the change in WR was -12% +/- 8% in group A and -5% +/- 13% in group B (P < 0.05), and the change in plasma BNP was -100 +/- 83 pg/mL in group A and -43 +/- 97 pg/mL in group B (P < 0.05). The degree of change in LVEDV, LVESV, and LVEF in group A tended to be better than that in group B, but these changes were not statistically significant. Moreover, there were significant correlations between changes in the (123)I-MIBG scintigraphic findings and changes in the LVEDV (% denervation, r = 0.692, P < 0.001; H/M ratio, r = -0.437, P < 0.05; and WR, r = 0.505, P < 0.01) or the LVESV (% denervation, r = 0.663, P < 0.001; H/M ratio, r = -0.438, P < 0.05; and WR, r = 0.532, P < 0.01) in group A. In contrast, there was no relationship between these parameters in group B. CONCLUSION: These findings indicate that the combination of spironolactone and candesartan may be more beneficial for CSNA and LV performance than candesartan alone in patients with CHF.     

Addition of valsartan to an angiotensin-converting enzyme inhibitor improves cardiac sympathetic nerve activity and left ventricular function in patients with congestive heart failure.

We determined whether the addition of the angiotensin-receptor blocker valsartan to an angiotensin-converting enzyme (ACE) inhibitor improves cardiac sympathetic nerve activity and left ventricular function in patients with congestive heart failure (CHF). METHODS: Thirty-two patients with CHF (left ventricular ejection fraction [LVEF] < 40%; mean, 33% +/- 6%) were treated with an ACE inhibitor and a loop diuretic. Sixteen patients (group A) were randomized to additionally receive valsartan (40-80 mg/d), and the remaining 16 patients (group B) continued their current regimen. Patients were studied before and 6 mo after treatment. The delayed heart-to-mediastinum count ratio (H/M ratio), delayed total defect score (TDS), and washout rate (WR) were determined from (123)I-metaiodobenzylguanidine images. The left ventricular end-diastolic volume (LVEDV) and LVEF were determined by echocardiography, and New York Heart Association (NYHA) functional class was estimated. RESULTS: Before treatment, TDS, H/M ratio, WR, LVEDV, LVEF, and NYHA functional class were similar in both groups. After treatment in group A, TDS decreased from 37 +/- 8 to 31 +/- 9 (P < 0.001), H/M ratio increased from 1.66 +/- 0.23 to 1.81 +/- 0.23 (P < 0.001), and WR decreased from 47% +/- 9% to 39% +/- 10% (P < 0.01). In addition, the LVEDV decreased from 193 +/- 36 mL to 169 +/- 51 mL (P < 0.005), and LVEF increased from 32% +/- 7% to 41% +/- 13% (P = 0.0005). In group B, these parameters did not change significantly. NYHA functional class improved in both groups (in group A, from 3.3 +/- 0.5 to 1.7 +/- 0.6 [P < 0.0005]; in group B, from 3.3 +/- 0.5 to 2.4 +/- 0.6; [P < 0.005]). The improvement was significantly greater in group A than in group B (P < 0.05). CONCLUSION: The addition of valsartan to an ACE inhibitor improves cardiac sympathetic nerve activity, left ventricular function, and symptoms in patients with CHF.     

Relationship between late ventricular potentials and myocardial 123I-metaiodobenzylguanidine scintigraphy in patients with dilated cardiomyopathy with mild to moderate heart failure: results of a prospective study of sudden death events

Purpose

Late ventricular potentials (LPs) are considered to be useful for identifying patients with heart failure at risk of developing ventricular arrhythmias. ¹²³I-metaiodobenzylguanidine (MIBG) scintigraphy, which is used to evaluate cardiac sympathetic activity, has demonstrated cardiac sympathetic denervation in patients with malignant ventricular tachyarrhythmias. This study was undertaken to clarify the relationship between LPs and ¹²³I-MIBG scintigraphy findings in patients with dilated cardiomyopathy (DCM).

Methods

A total of 56 patients with DCM were divided into an LP-positive group (n?=?24) and an LP-negative group (n?=?32). During the compensated period, the delayed heart/mediastinum count (H/M) ratio, delayed total defect score (TDS), and washout rate (WR) were determined from ¹²³I-MIBG images and plasma brain natriuretic peptide (BNP) concentrations were measured. Left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), and left ventricular ejection fraction (LVEF) were simultaneously determined by echocardiography.

Results

LVEDV, LVESV, LVEF and plasma BNP concentrations were similar in the two groups. However, TDS was significantly higher (35?±?8 vs. 28?±?6, p?p?p?p?p?p?Conclusion The present study demonstrated that the values of cardiac ¹²³I-MIBG scintigraphic parameters were worse in LP-positive DCM patients than in LP-negative DCM patients. Furthermore, in LP-positive DCM patients with a high WR, the incidence of sudden death events was higher than that in other subgroups of DCM patients.     

Assessment of myocardial washout of Tc-99m-sestamibi in patients with chronic heart failure: comparison with normal control

BACKGROUND: In contrast to 201TlCl, 99mTc-sestamibi shows very slow myocardial clearance after its initial myocardial uptake. In the present study, myocardial washout of 99mTc-sestamibi was calculated in patients with non-ischemic chronic heart failure (CHF) and compared with biventricular parameters obtained from first-pass and ECG-gated myocardial perfusion SPECT data. METHODS AND RESULTS: After administration of 99mTc-sestamibi, 25 patients with CHF and 8 normal controls (NC) were examined by ECG-gated myocardial perfusion SPECT and planar data acquisition in the early and delayed (interval of 3 hours) phase. Left ventricular ejection fraction (LVEF, %), peak filling rate (PFR, sec(-1)), end-diastolic volume (LVEDV, ml) and end-systolic volume (LVESV, ml) were automatically calculated from the ECG-gated SPECT data. Myocardial washout rates over 3 hours were calculated from the early and delayed planar images. Myocardial washout rates in the CHF group (39.6+/-5.2%) were significantly higher than those in the NC group (31.2+/-5.5%, p < 0.01). The myocardial washout rates for the 33 subjects showed significant correlations with LVEF (r = -0.61, p < 0.001), PFR (r = -0.47, p < 0.01), LVEDV (r = 0.45, p < 0.01) and LVESV (r = 0.48, p < 0.01). CONCLUSION: The myocardial washout rate of 99Tc-sestamibi is considered to be a novel marker for the diagnosis of myocardial damage in patients with chronic heart failure.     

<Superscript>123</Superscript>I-MIBG imaging can be used to evaluate microvascular disturbance caused by embolization by microdebris after rotational atherectomy

Background During rotational atherectomy (RA), the coronary atherosclerotic plaque is largely pulverized into microdebris, which may cause serious hemodynamic instability owing to significant segmental left ventricular asynergy embolization of the distal microvasculature by atheromatous debris and associated vasospasm. Objective To evaluate the usefulness of ¹²³I-metaiodobenzylguanidine (¹²³I-MIBG) in the examination of microvascular embolization after RA. Methods and results Nineteen patients with stable effort angina pectoris who had undergone RA were evaluated in this study. Left ventricular ejection fraction (LVEF) was determined by left ventriculography immediately before and after RA. The serum concentration of creatine phosphokinase (CPK), creatine phosphokinase-myocardial band (CPK-MB) isozyme, and cardiac troponin-T was determined after RA. ^99mTc-methoxyisobutylisonitrile (^99mTc-MIBI) and ¹²³I-MIBG scintigraphic examinations were also performed 1 day after RA. The regional defect score (RDS) was determined from ^99mTc-MIBI scintigraphic findings, while early and delayed RDS, heart-to-mediastinum count ratios (H/M ratios), and washout rate (WR) were determined from ¹²³I-MIBG scintigraphy. After RA, the left ventriculographic LVEF mildly decreased by ≤10% in ten patients (group A), but it decreased by >10% in the remaining nine patients (group B). There were no differences in baseline clinical characteristics between the two groups. The CPK, CPK-MB isozyme, troponin-T, RDS by ^99mTc-MIBI, H/M ratios, and WR after RA were similar in the two groups. However, the RDSs determined from early and delayed ¹²³I-MIBG in group A were significantly lower than those in group B (4.5 ± 3.8 vs. 13.4 ± 10.8, P < 0.05; 9.0 ± 6.3 vs. 17.7 ± 10.0, P < 0.05, respectively). Moreover, there were significant correlations between delta LVEF and troponin-T (r = 0.54, P < 0.05) and RDSs of early and delayed ¹²³I-MIBG (r = 0.46, P < 0.05; r = 0.64, P < 0.05, respectively). Conclusions These findings suggest that ¹²³I-MIBG imaging can be used to evaluate microvascular disturbance caused by embolization by microdebris after RA.     

Effect of acute postinfusion lipemia and free fatty acids on myocardial contractility: Assessment with radionuclide ventriculography

Equilibrium gated radionuclide ventriculography was used to evaluate the effect of intravenous fat-emulsion overload and excess of free fatty acids (FFA) on left ventricular ejection fraction (LVEF) in 20 patients with and without coronary artery disease (CAD). Fifteen of these patients had normal (>50%) baseline LVEF and 5 had low (<50%) baseline LVEF. From 100 to 150 ml of 20% artificial fat emulsion (Liposyn) was infused over 20–25 min. At the end of the infusion, triglyceridemia reached 820±220 mg% and left ventricular ejection fraction decreased from baseline 62±19% (mean±SD) to 58±16% (P<0.05, paired t-test). After completion of Liposyn infusion, 5,000 U of heparin was administered intravenously and monitoring of LVEF was continuod. One and one-half hours following heparin administration, plasma FFA levels reached 3.7+2.0 mmol/l and LVEF rose to 69±19% (P<0.001, paired t-test). Our data indicate that acute intravenous fat overload can suppress and high pathophysiologic levels of FFA can increase LVEF. This effect is more uniform and statistically more reliable in patients with normal LVEF. The study failed to demonstrate any significant difference in the effect of this pharmacologic intervention between patients with and without CAD.     

动脉导管未闭手术前后左室功能的对比

应用超声心动图测量儿童和成人各３６例动脉导管未闭患者．（ＰＤＡ）在手术前后左室舒张末期内径和收缩末期内径。应用Ｃｕｂｅ公式自动计算出左室舒张末期容积,收缩末期容积、每搏搏出量、射血分数、和短轴缩短率。将手术前后两组测量数据分别用统计学配对ｔ检验,再对两组手术前后ＬＶＥＤＶ指数进行对比。结果表明,两组手术后ＬＶＥＤＤ、ＬＶＥＤＶ、ＬＶＥＳＶ、ＬＶＳＶ、ＬＶＥＦ和ＬＶＦＳ均有不同程度变化,两者差异显著     

Development and application of normal limits for left ventricular ejection fraction and volume measurements from 99mTc-sestamibi myocardial perfusion gates SPECT.

Gated SPECT is a reproducible method for assessing left ventricular volume (LVV) and left ventricular ejection fraction (LVEF) from 99mTc-sestamibi myocardial perfusion imaging studies. LVV and LVEF measurements by this approach correlate well with those obtained from other cardiovascular imaging techniques. Nevertheless, the lack of criteria for abnormal test findings has limited the potential clinical application of this new imaging technique. METHODS: Gated SPECT measurements were evaluated for 214 patients with a low Bayesian likelihood (< 10%) of coronary artery disease (CAD) before performance of 99mTc-sestamibi stress-rest myocardial perfusion SPECT. The patients were grouped into normotensive patients (n = 98), hypertensive patients without left ventricular hypertrophy (LVH) (n = 80), and hypertensive patients with LVH on resting electrocardiography (n = 36). Gated SPECT measurements for left ventricular end-diastolic volume (LVEDV) index, left ventricular end-systolic volume (LVESV) index, and LVEF were obtained according to a published method, using a modified Simpson's rule technique. RESULTS: Similar results were obtained for mean LVV and LVEF measurements between normotensive patients and hypertensive patients without LVH. Hence, these groups were combined (as group 1). By contrast, hypertensive patients with LVH (group 2), had significantly lower LVEF values (P = 0.01) and higher mean LVESV index values than normotensive patients (P = 0.03). Sex differences were marked: women had significantly higher mean resting LVEF values than men (P < 0.0001) and significantly lower mean resting LVEDV index values (P < 0.0001). A significant relationship was seen between LVEDV index and LVEF (r = -0.60; P < 0.0001) and between LVEDV index and heart rate (r = -0.26; P < 0.001). The normal limits were LVEF > or = 41% in men and > or = 49% in women, LVEDV index < or = 76 mL/m2 in men and < or = 57 mL/m2 in women, and LVESV index < or 38 mL/m2 in men and < or =26 mL/m2 in women. Among hypertensive patients, 22% with LVH had an abnormally low LVEF and 19% had an increased LVEDV index according to these test criteria. By contrast, no hypertensive patients without LVH had an abnormally low LVEF, and only 6% had volume abnormalities. CONCLUSION: Using a cohort of low-likelihood patients, we generated sex-specific normal limits for LVV and LVEF for myocardial perfusion gated SPECT. Application of these findings resulted in the detection of occult left ventricular dysfunction in approximately one fifth of hypertensive patients for whom concomitant LVH was found through resting electrocardiography. These normal limits can now be evaluated prospectively for their potential clinical value.     

三平面组织同步成像定量评价冠心病患者左心室节段非同步运动

目的 探讨三平面组织同步成像技术定量评价冠心病患者左心室节段收缩非同步性运动及其与左心室收缩功能的关系.资料与方法 34例冠心病患者和35例正常对照者,应用三平面组织同步成像技术获得心尖四腔切面组织速度图,获取左心室6个壁共12个节段的收缩期达峰时间(Tp)、达峰速度(Vp),并计算Tp、Vp的标准差(Tp-SD、Vp-SD)及12个节段中任意2个节段Tp、Vp的最大差值( Tp-maxD、Vp-maxD).同时采用Simpson双平面法测量左室射血分数(LVEF)、左室舒张末期容积(LVESV)、左室收缩末期容积(LVEDV).结果 冠心病组LVEDV、LVESV较正常对照组增加,LVEF较正常对照组减小,差异均有统计学意义(P＜ 0.001).与正常对照组相比,冠心病组Tp、Tp-SD、Tp-maxD均明显延迟,Vp、Vp-SD、Vp-maxD均明显降低(P＜0.001);Tp与LVEF呈负相关(r=-0.559,P＜0.001);Vp与LVEF呈正相关(r=0.801,P＜ 0.001).结论 三平面组织同步成像可用于定量评价冠心病患者左心室非同步运动,Tp、Tp-SD、Tp-maxD、Vp、Vp-SD、Vp-maxD 可作为定量评价左室收缩运动同步性的有效指标,且左室运动同步性异常加重左室收缩功能异常.     

PCI术后2型糖尿病合并冠心病患者心功能分级与hs-CRP水平及预后的相关性研究

 目的 探讨2型糖尿病患者经皮冠状动脉介入术(percutaneous coronary intervention,PCI)后高敏C反应蛋白(high-sensitivity C-reactive protein,hs-CRP)水平与心功能不全及预后的相关性。方法 选择符合纳入标准的PCI后合并2型糖尿病心功能不全患者120例,选择同期健康体检者42名为对照组,收集研究对象血脂、hs-CRP、脑钠素(Brain natriuretic peptide,BNP)、超声心动相关指标等临床基线资料。进行1年的随访,包括死亡、心肌梗死、脑卒中和再次血运重建等主要不良心脑血管事件(main adverse cardiovascular and cerebrovascular events, MACCE),并对数据进行统计学分析。结果 入选的心功能不全患者按照美国NYHA心功能分级标准:(Ⅰ级+Ⅱ级)为C组,Ⅲ级为D组,Ⅳ 级为E组,此三组的hs-CRP, BNP,左室舒张末容积(left ventricular end diastolic volume,LVEDV)、左室收缩末容积(left ventricular end systolic volume,LVESV),明显高于对照组,差异有统计学意义(P<0.05);而其随着心功能分级的增加,其数值逐步增加,各组间比较有统计学意义,心功能不全的三组左室射血分数 (left ventricular ejection fraction,LVEF)显著低于对照组,而其随着心功能分级的增加,其数值逐步降低,各组间比较差异有统计学意义P<0.05;通过直线回归分析,hs-CRP的水平和BNP呈正相关(r=0.52,P<0.05);而和LVEF呈负相关,(r=-0.67,P<0.05);hs-CRP和LVEDV,LVESV无相关;BNP和LVEDV,LVESV呈正相关(r=0.42,P<0.05; r=0.39, P<0.05);和LVEF呈负相关(r=-0.78,P<0.05)。故BNP在诊断和评价心力衰竭时优于hs-CRP。按是否出现MACCE分组后,进一步行多因素logistic回归分析,显示hs-CRP、BNP 为患者发生MACCE的独立预测因子(P<0.05)。结论 hs-CRP是发生心功能不全的独立预测因子, 能有效评估心功能不全的发病风险及其预后,故hs-CRP检测对评估心血管疾病具有很好的应用价值。     

31P-MR spectroscopic imaging in hypertensive heart disease

Hypertensive heart disease (HHD) causes structural changes (e.g., fibrosis) that result in diastolic and systolic myocardial dysfunction. Alterations of ³¹P metabolism and cardiac energy impairments were assessed in patients with HHD by MR spectroscopy (MRS) and correlated with left ventricular systolic function. Thirty-six patients with HHD and 20 healthy controls (mean age 35.2±10.7 years) were examined with ³¹P-MRS at 1.5 T by using an ECG-gated CSI sequence. Twenty-five patients (mean age 64.3±9.3 years) had diastolic dysfunction, but preserved systolic function (HHD-D), whereas 11 patients (62.3±11.4 years) suffered from additional impaired systolic function (HHD-S). In both patient groups, the PCr/γ-ATP ratio was lower than in the controls (controls: 2.07±0.17; P<0.001), and in HHD-S was lower than in HHD-D (1.43±0.21 vs. 1.65±0.25; P=0.012). PCr/γ-ATP ratios were linearly correlated with LVEF (Pearson's r: 0.39; P=0.025). In the HHD-S group, the PDE/γ-ATP ratio was significantly lower (0.56±0.36) than in the controls (1.14±0.42; P=0.001). In contrast to the group of HHD-D patients, whose slightly decreased PCr/γ-ATP ratios compared to controls may be explained by age differences, the more distinct changes observed in HHD-S patients indicate an altered energy metabolism. The observed metabolic changes were related to functional impairments, as indicated by a reduced LVEF. Reduced PDE/ATP ratios indicate changes in the phospholipid metabolism.     

Radionuclide ejection fraction: Comparison of response to treadmill and bicycle exercise

Most exercise radionuclide studies utilise the supine bicycle ergometer during imaging, although exercise on a treadmill results in greater cardiovascular stress. Twenty-three patients were studied to compare the radionuclide left ventricular ejection fraction (LVEF) estimated immediately following treadmill exercise with that obtained at peak supine bicycle exercise in patients with coronary artery disease (CAD) and patients with normal coronary arteries.In 14 patients with CAD the rest LVEF was 47±7% (mean±SD) by first pass and 49±10% by equilibrium blood pool techniques. Immediately following maximum treadmill exercise, 13 of the 14 patients with coronary artery disease showed either no change or a decrease in LVEF, the LVEF was 49±7% (P=NS) and 47±8% (P=NS) by first pass and equilibrium determinations respectively. In comparison the LVEF during peak supine bicycle exercise decreased significantly to 42±12% (P<0.01). In nine patients with angiographically normal coronary arteries the rest LVEF was 51±4% by first pass and 54±6% by equilibrium, increasing to 67±7% (P<0.01) and 64±7% (P<0.01) respectively following treadmill exercise. During peak bicycle exercise LVEF increased in the normal patients to 61±7% (P<0.05).These data suggest that quantitative radionuclide angiography following either maximum treadmill exercise or during peak bicycle exercise can discriminate between patients with coronary artery disease and normal subjects, although the magnitude of left ventricular functional changes are greater during bicycle stress.     

多层螺旋CT与M型超声心动图评估左室功能的对照研究

目的：用多层螺旋CT（multi-detector row computed tomography,MRCT）测量并评估左室功能的各项参数,并与M型超声心动图测量得到的结果进行比较。方法：62位冠心病或可疑患有冠心病的患者（男性40人、女性22人,平均年龄64.2±11.1岁）在24h内接受回顾性心电门控16通道MRCT心脏增强扫描及心脏M型超声心动图检查。在GEAW4.1CT工作站上测量出每位患者的左室舒张末期容积（LVEDV）、左室收缩末期容积（LVESV）并根据公式（LVEDV-LVESV）/LVEDV×100%计算出左室射血分数（LVEF）,并用简单直线回归分别分析MRCT测量所得参数与M型超声心动图测得结果的相关性。结果：16层CT测得的LVEDV为125.4±62.1ml、LVESV为52.8±59.3ml、LVEF为62.9±13.4%,与M型超声心动图测量结果（Teichholz校正公式法）有很好的相关性〔LVEDV为112.8±49.7ml（r=0.826,P〈0.001）、LVESV为45.9±47.0ml（r=0.960,P〈0.001）、LVEF为64.8±13.9%（r=0.916,P〈O．001）]。结论：回顾性心电门控MRCT心脏增强扫描可以应用于临床心功能的评估诊断。     

Comparative assessment of rest and post-stress left ventricular volumes and left ventricular ejection fraction on gated myocardial perfusion imaging (MPI) and echocardiography in patients with transient ischaemic dilation on adenosine MPI: Myocardial stunning or subendocardial hypoperfusion?

Background

Transient ischaemic dilation (TID) on myocardial perfusion imaging (MPI) is an important finding, conveying a high risk of subsequent cardiac events. However, the mechanism leading to TID on MPI is not well elucidated. This study aimed to determine if TID is due to true LV cavity dilation and ventricular stunning, or is due to relative subendocardial hypoperfusion.

Methods

31 patients undergoing single-day Tc-99m adenosine sestamibi MPI were recruited. All had routine ECG-gated single-day rest-stress adenosine MPI, with transthoracic echocardiograms (echo) acquired concurrently at rest, and both immediately, and 2?hours, post-stress. Echocardiography was performed using a Vivid-7 (GE). LV volumes and LVEF were quantified blinded to MPI results, using biplane Simpson method on echo, and quantitatively (including TID) with QGS^?, on MPI.

Results

Patients were divided into quartiles for TID, with the top quartile considered TID positive [TID+ 9/31 (TID ratio 1.3?±?0.09)], and TID negative [TID? 22/31 (TID ratio 1.01?±?0.04)]. There was good correlation between resting echo and MPI physical measurements (LVEDV r ²?=?0.79, LVESV r ²?=?0.9, and LVEF r ²?=?0.75). On MPI, a significant drop in LVEF was observed between rest and early stress in the TID+ group (56.6% vs 46.5%, P?<?.002), as well as an increase in both LVESV (62 vs 79?mls, P?<?.0001) and LVEDV (113 vs 131?mls, P?<?.0001). However, no statistically significant change in LVEF, LVESV or LVEDV was identified on concurrent echo imaging (LVEF 57% vs 56%, P?<?.66; LVESV 48 vs 54?mls, P?<?.26; LVEDV 87 vs 97?mls, P?<?.299). No significant change in LVEF or ventricular volumes was noted in the TID? group by either echo or MPI.

Conclusion

Transient dilation of the left ventricle on adenosine MPI is not related to chamber enlargement and myocardial stunning, but is more likely a function of subendocardial hypoperfusion and impaired coronary flow reserve.     

Automatic computation of left ventricular ejection fraction from spatiotemporal information in cine-SSFP cardiac MR images

PURPOSE: To clinically validate an algorithm that automatically computes left ventricular (LV) ejection fraction (LVEF) using a priori geometric and intrinsic spatiotemporal information from cine steady-state free precession (SSFP) MR images. MATERIALS AND METHODS: The algorithm was evaluated in 64 subjects (21 healthy volunteers and 43 patients, LVEF 19-71%). Bland-Altman analyses were performed on short-axis slices subdivided into three sections (basal, midcavity, and apical) to assess the impact of morphologic variations on LVEF computation. RESULTS: The automated algorithm delineated the clinically applicable endocardial boundary in 1011 of 1078 short-axis slices (94%). The bias (mean difference) values computed with clinically unusable contours replaced with hand-drawn equivalents were small for the LV end-diastolic volume (LVEDV, <11 mL/7%), end-systolic volume (LVESV, <7 mL/11%), and LVEF (<1.2%). Moreover, these values were within the limits of interobserver and intraobserver variability of experienced observers (LVEDV, <13 mL/8%; LVESV, <12 mL/17%; and LVEF, <5%). In the end-diastolic phase, the limits of agreement (bias +/- 1.96 SD of difference) were small (<5% LVEDV) in all sections. However, in the end-systolic phase, the limits of agreement were larger for the midcavity (<21% LVESV) and apical (<11% LVESV) slices. CONCLUSION: This data-driven algorithm can estimate LVEDV, LVESV, and LVEF with a bias that is comparable to the interobserver and intraobserver variability of experienced observers.     

门控心肌灌注显像评估慢性心力衰竭患者左心室机械同步性的应用及其与纽约心功能分级的关系

目的 探讨门控心肌灌注显像（GMPI）在评估慢性心力衰竭患者左心室机械同步性中的应用价值及其与纽约心功能分级的关系,分析慢性心力衰竭患者发生左心室机械同步性失调的影响因素。 方法 回顾性分析2020年1月至2021年12月在昆明医科大学附属延安医院行GMPI检查的81例慢性心力衰竭患者的临床资料,其中男性56例、女性25例,年龄（56.1±15.6）岁,同时纳入同期就诊的23名健康受检者为健康对照组,采集所有研究对象的GMPI指标[包括左心室射血分数（LVEF）、高峰充盈率（PFR）、左心室收缩末期容积（LVESV）、左心室舒张末期容积（LVEDV）、相位分布标准差（PSD）、相位直方图带宽（PHB）、静息总积分（SRS）]和实验室检查结果[包括超敏C反应蛋白（Hs-CRP）、N末端B型利钠肽原（NTpro-BNP）],GMPI检查和实验室检查的时间间隔不超过7 d。通过Kruskal Wallis检验与Spearman相关性分析法分析GMPI各指标、Hs-CRP、NTpro-BNP与慢性心力衰竭患者纽约心功能分级的关系。2组间独立样本的比较采用 t 检验或Mann-Whitney U 检验,计数资料的组间比较采用卡方检验或Fisher确切概率法。通过Logistic回归分析探讨不同因素对慢性心力衰竭患者左心室机械同步性的影响。 结果 LVEF、LVEDV、LVESV、PFR、PHB、PSD、Hs-CRP、NTpro-BNP在心功能Ⅰ级组、心功能Ⅱ级组、心功能Ⅲ~Ⅳ级组间的差异均有统计学意义（H=23.846、14.791、21.089、6.251、18.892、20.347、19.171、35.654,均P<0.05）;心功能Ⅰ级组慢性心力衰竭患者与健康对照组相比,LVEF、LVEDV、LVESV、PFR、PSD、NTpro-BNP间的差异均有统计学意义（t=4.084,Z=3.462、3.038、3.519、3.489、2.203,均P<0.05）。SRS、LVESV、LVEDV、PHB、PSD、NTpro-BNP、Hs-CRP水平与纽约心功能分级呈正相关（r=0.235、0.547、0.474、0.481、0.458、0.671、0.439,均P<0.05）;LVEF、PFR与纽约心功能分级呈负相关（r=−0.563、−0.304,均P<0.05）。单因素分析结果显示,左心室机械同步与不同步的慢性心力衰竭患者的年龄、LVEF、PFR、心率、LVEDV、LVESV、SRS、Hs-CRP、NTpro-BNP比较,差异均有统计学差异（t=2.550、χ2=6.146、t=4.042、Z=3.149、χ2=5.335、χ2=5.993、Z=4.978、χ2=6.154、Z=4.381,均P<0.05）;多因素Logistic回归分析结果显示,LVEF、SRS是慢性心力衰竭患者发生左心室机械同步性失调的独立影响因素（B=−0.166、0.278,B值标准误为0.068、0.130,Wald χ2=5.927、4.584,P=0.015、0.032,OR=0.847、1.320,95%CI：0.741~0.968、1.024~1.702）。 结论 LVEF、LVEDV、LVESV、PFR、PSD、NTpro-BNP可能具有早期诊断慢性心力衰竭的潜在价值;LVEF、LVESV、PFR、LVEDV、PHB、PSD、NTpro-BNP、Hs-CRP对慢性心力衰竭患者的心功能受损严重程度有提示作用,以NTpro-BNP、LVEF、LVESV的提示作用较优;SRS水平升高、LVEF水平降低是慢性心力衰竭患者发生左心室机械同步性失调的独立预测因子。     

<Superscript>123</Superscript>I-BMIPP delayed scintigraphic imaging in patients with chronic heart failure

Objective  The objective of the present study was to clarify the ability of ¹²³I-beta-methyl-iodophenylpentadecanoic acid (¹²³I-BMIPP) to evaluate the heart-to-mediastinum (H/M) ratio and myocardial global washout rate (WR) in patients with chronic heart failure (CHF). Methods  The severity of CHF was evaluated on the basis of the New York Heart Association (NYHA) classification. Twenty patients with CHF (13 with idiopathic dilated cardiomyopathy and 7 with ischemic cardiomyopathy) and 11 age-matched controls underwent myocardial radionuclide imaging. Scintigraphic images were obtained from each participant at the early (30 min following radio-isotope injection) and late (4 h) phases using ¹²³I-BMIPP. The H/M ratio and WR were calculated from planar images. Concentrations of plasma brain natriuretic peptide (BNP) were measured prior to the scintigraphic study. Results  The ¹²³I-BMIPP uptake of early H/M and global WR did not significantly differ among groups, but uptake of delayed H/M was significantly lower in patients with NYHA class III than in controls (control 2.47 ± 0.39; class III 1.78 ± 0.28, P < 0.05). The uptake of delayed H/M and global WR correlated with plasma log BNP in all participants (r = −0.38, P < 0.05; 0.43, P < 0.05, respectively). Conclusions  These data suggest that ¹²³I-BMIPP uptake of delayed H/M enhances the image of CHF severity. The myocardial WR of ¹²³I-BMIPP also effectively depicted the severity of CHF.     

Measurement of left ventricular ejection fraction with ionic 113mIn and a cardiac probe

Left ventricular ejection fraction (LVEF) was measured with a cardiac probe (Nuclear Stethoscope, Bios Inc., Valhalla, New York) and ^113mIn in 28 normal subjects and 86 patients with coronary artery disease (CAD). In 20 normal subjects ^99mTC-RBCs were compared with ^113mIn which binds to transferrin after IV injection. With ^99mTc-RBCs, average LVEF was 57±7% (1 SD); with ^113mIn, average LVEF was 55±8% (N.S.). Sequential measurements at different times over 60 min revealed good reproducibility.Comparison of LVEFs obtained using ^99mTc-RBCs with a gamma camera and cardiac probe revealed a good correlation. The correlation coefficients were 0.92 in 25 patients with CAD and 0.95 in 10 patients with LV wall motion abnormalities.The LVEF obtained using a cardiac probe and ^113mIn increased in 28 normals from 57±9% to 64±13% (P<0.001) during handgrip exercise, while the LVEF decreased from 45±9% to 41±10% (P<0.01) in patients with acute myocardial infarction 4–7 weeks after episode, from 48±11 to 40±12% (P<0.001) in patients with old myocardial infarction, and from 52±9 to 42±9% (P<0.001) in patients with angina pectoris.The cardiac probe and ^113mIn provide a useful alternate means of determining left ventricular dysfunction in facilities where ^99mTc and a gamma camera computer system are not readily available.This work supported in part by USPHS Grant No. GM10548.